Download a tar.bz2 of the subversion code from here.
You can download the current development version of g4c from the public SVN repository doing:
$ svn co https://svn.sourceforge.net/svnroot/g4c/trunk g4c
We use autotools so the way to compile the program is the same as in other projects:
$ cd g4c
$ ./configure
$ make
# make install
This is a demostration video where you can see g4c recording simulteanously in two recorders different ISO images and a little tour throught the program.